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91.
92.
S?ren?Emil?S?rensenEmail author Michael?R.?Hansen Morten?K.?Ebbesen Ole??.?Mouritsen 《Structural and Multidisciplinary Optimization》2012,45(6):907-916
Poor dynamics owing to polygon action is a known concern in mechanical applications of closed articulated chains. In this
paper a kinematic model of the polygon action in large chains of loop-sorting-systems is proposed. Through optimization techniques
the chain dynamics is improved by minimizing the polygon action using a parametric model of the track layout as design variables.
Three formulations of the kinematic polygon action are tested on an average sized planer tracks layout to find a superior
model. Verification of the proposed optimization method is performed using a state-of-the-art multi-body simulation model
of the chain dynamics. 相似文献
93.
A small scanning three-wavelength lidar system at NASA Langley Research Center in Hampton, Virginia, has been used since 1992 to make atmospheric measurements on stratospheric and upper tropospheric aerosols and on the evolution of aircraft exhaust plumes. Many of these measurements have been made away from the zenith, and, to reduce the hazard to air traffic produced by the laser beam, a radar safety device has been installed. The radar application is original in that the radar beam is made collinear with the laser beam by use of a dichroic mirror that transmits the laser radiation and reflects the microwaves. This mirror is inserted into the outgoing optical path prior to the radiation from both the radar and the laser passing through the independent scanning unit. Tests of the complete system show that the lidar and radar beams remain collocated as they are scanned and that the radar can be used to inhibit the laser prior to an aircraft passing through the beam. 相似文献
94.
H. Hansen 《Starch - St?rke》1974,26(11):390-392
Storage of potatoes in controlled atmosphere. The interim results obtained from trials with CA-storage are reported. Storage atmospheres with low O2 and increased CO2 contents largely inhibit the sprout growth of potatoes kept at a temperature of 9 °C so that chemical sprout suppressants may possibly be dispensable. Storage atmospheres with too high a CO2 content cause an intense rise of the saccharose content and lead to increased decay. With tolerable storage atmospheres these disadvantages can be avoided. The remaining questions shall be answered in further trials which shall also help to bring CA-storage to perfection for its application in practice. 相似文献
95.
Songyu Dong Weili Zheng Nicholas Pinkerton Jacob Hansen Svetlana B. Tikunova Jonathan P. Davis Sarah M. Heissler Elena Kudryashova Edward H. Egelman Dmitri S. Kudryashov 《International journal of molecular sciences》2022,23(13)
Due to its essential role in cellular processes, actin is a common target for bacterial toxins. One such toxin, TccC3, is an effector domain of the ABC-toxin produced by entomopathogenic bacteria of Photorhabdus spp. Unlike other actin-targeting toxins, TccC3 uniquely ADP-ribosylates actin at Thr-148, resulting in the formation of actin aggregates and inhibition of phagocytosis. It has been shown that the fully modified F-actin is resistant to depolymerization by cofilin and gelsolin, but their effects on partially modified actin were not explored. We found that only F-actin unprotected by tropomyosin is the physiological TccC3 substrate. Yet, ADP-ribosylated G-actin can be produced upon cofilin-accelerated F-actin depolymerization, which was only mildly inhibited in partially modified actin. The affinity of TccC3-ADP-ribosylated G-actin for profilin and thymosin-β4 was weakened moderately but sufficiently to potentiate spontaneous polymerization in their presence. Interestingly, the Arp2/3-mediated nucleation was also potentiated by T148-ADP-ribosylation. Notably, even partially modified actin showed reduced bundling by plastins and α-actinin. In agreement with the role of these and other tandem calponin-homology domain actin organizers in the assembly of the cortical actin network, TccC3 induced intense membrane blebbing in cultured cells. Overall, our data suggest that TccC3 imposes a complex action on the cytoskeleton by affecting F-actin nucleation, recycling, and interaction with actin-binding proteins involved in the integration of actin filaments with each other and cellular elements. 相似文献
96.
Lisby T. Nikles S.A. Najafi K. Hansen O. Bouwstra S. Branebjerg J.A. 《Journal of microelectromechanical systems》2004,13(3):452-464
A variety of different silicon structures has been fabricated and characterized mechanically to optimize the design of silicon ribbon cables used in neural probes and multichip packaging structures. Boron-doped 3-/spl mu/m-thick silicon beams were tested in three modes: bending in plane, twisting (along beam axis), and pushing. Various cable configurations were investigated (straight beams, curved beams, meandered beams, etc.) as well the effects of length, width, cable termination, and the presence of reinforcing spans between multistranded cables. The results along with finite element modeling indicated that many simple modifications could be made to increase the strength and flexibility of silicon ribbon cables. One structure, a meandered beam 200-/spl mu/m wide and 2-mm long could be twisted up to 712/spl deg/. It also was seen that structures having multiple 20-/spl mu/m-wide beams were generally more robust than those with a single 500-/spl mu/m-wide beam. Finally, a method for easy determination of the bending fracture strain is analyzed and verified. It was seen that the silicon structures tested broke after a strain slightly above 2%. 相似文献
97.
Yafeng Lu Rolando Garcia Brett Hansen Michael Gleicher Ross Maciejewski 《Computer Graphics Forum》2017,36(3):539-562
Predictive analytics embraces an extensive range of techniques including statistical modeling, machine learning, and data mining and is applied in business intelligence, public health, disaster management and response, and many other fields. To date, visualization has been broadly used to support tasks in the predictive analytics pipeline. Primary uses have been in data cleaning, exploratory analysis, and diagnostics. For example, scatterplots and bar charts are used to illustrate class distributions and responses. More recently, extensive visual analytics systems for feature selection, incremental learning, and various prediction tasks have been proposed to support the growing use of complex models, agent‐specific optimization, and comprehensive model comparison and result exploration. Such work is being driven by advances in interactive machine learning and the desire of end‐users to understand and engage with the modeling process. In this state‐of‐the‐art report, we catalogue recent advances in the visualization community for supporting predictive analytics. First, we define the scope of predictive analytics discussed in this article and describe how visual analytics can support predictive analytics tasks in a predictive visual analytics (PVA) pipeline. We then survey the literature and categorize the research with respect to the proposed PVA pipeline. Systems and techniques are evaluated in terms of their supported interactions, and interactions specific to predictive analytics are discussed. We end this report with a discussion of challenges and opportunities for future research in predictive visual analytics. 相似文献
98.
The first data transmission over air-guiding photonic bandgap (PBG) fibre is demonstrated. A 10 Gbit/s signal was successfully transmitted at 1550 nm over 150 m of singlemode PBG fibre, thus demonstrating their applicability to optical communications. Furthermore, the impact of the polarisation properties of PBG fibres is highlighted experimentally. 相似文献
99.
Frederik J. Hansen Zhiyuan Wu Paul David Anke Mittelstdt Anne Jacobsen Malgorzata J. Podolska Kenia Ubieta Maximilian Brunner Dina Kouhestani Izabela Swierzy Lotta Roßdeutsch Bettina Klsch Isabella Kutschick Susanne Merkel Axel Denz Klaus Weber Carol Geppert Robert Grützmann Alan Bnard Georg F. Weber 《International journal of molecular sciences》2022,23(9)
Immunotherapy has become increasingly important in the treatment of colorectal cancer (CRC). Currently, CD73, also known as ecto-5′-nucleotidase (NT5E), has gained considerable interest as a potential therapeutic target. CD73 is one of the key enzymes catalyzing the conversion of extracellular ATP into adenosine, which in turn exerts potent immune suppressive effects. However, the role of CD73 expression on various cell types within the CRC tumor microenvironment remains unresolved. The expression of CD73 on various cell types has been described recently, but the role of CD73 on B-cells in CRC remains unclear. Therefore, we analyzed CD73 on B-cells, especially on tumor-infiltrating B-cells, in paired tumor and adjacent normal tissue samples from 62 eligible CRC patients. The highest expression of CD73 on tumor-infiltrating B-cells was identified on class-switched memory B-cells, followed by naive B-cells, whereas no CD73 expression was observed on plasmablasts. Clinicopathological correlation analysis revealed that higher CD73+ B-cells infiltration in the CRC tumors was associated with better overall survival. Moreover, metastasized patients showed a significantly decreased number of tumor-infiltrating CD73+ B-cells. Finally, neoadjuvant therapy correlated with reduced CD73+ B-cell numbers and CD73 expression on B-cells in the CRC tumors. As promising new immune therapies are being developed, the role of CD73+ B-cells and their subsets in the development of colorectal cancer should be further explored to find new therapeutic options. 相似文献
100.
Highly birefringent index-guiding photonic crystal fibers 总被引:10,自引:0,他引:10
Hansen T.P. Broeng J. Libori S.E.B. Knudsen E. Bjarklev A. Jensen J.R. Simonsen H. 《Photonics Technology Letters, IEEE》2001,13(6):588-590
Photonic crystal fibers (PCFs) offer new possibilities of realizing highly birefringent fibers due to a higher intrinsic index contrast compared to conventional fibers. In this letter, we analyze theoretically the levels of birefringence that can be expected using relatively simple PCF designs. While extremely high degrees of birefringence may be obtained for the fibers, we demonstrate that careful design with respect to multimode behavior must be performed. We further discuss the cutoff properties of birefringent PCFs and present experimental results in agreement with theoretical predictions on both single- and multimode behavior and on levels of birefringence 相似文献